What is WETH?

A brief overview of wETH and why you need it for decentralized platforms.

What is WETH?

Why You Need WETH

WETH, or Wrapped ETH, is an ERC-20 token that makes Ethereum's native ETH compatible with DeFi protocols. It enables seamless token swaps on DEXs like Uniswap, liquidity provision in pools on Aave (with over $20B TVL as of 2025), NFT auctions on OpenSea (handling 80% of Ethereum NFT volume), and on-chain marketplaces. Without WETH, native ETH can't interact with most smart contracts, limiting your participation in the $100B+ DeFi market.

WETH Explained: Definition and How It Works

WETH is Wrapped Ether, an ERC-20 token pegged 1:1 to ETH. Wrapping locks ETH in a smart contract (e.g., via Uniswap's interface) and mints equivalent WETH; unwrapping burns WETH to release ETH. This process is instant on L2s (under 1 second) and costs 50,000-100,000 gas on mainnet, preserving value minus fees (average $5-20 during low congestion).

ETH vs WETH: What’s the Difference?

ETH is Ethereum's native asset for gas fees (average 20-50 Gwei in 2025) and value transfer. WETH mirrors ETH's price but follows ERC-20 standards for dApp compatibility. Key diffs: ETH pays network fees (e.g., 0.001 ETH per tx); WETH enables DeFi yields (up to 5-10% APY in pools). Use WETH for 95% of Ethereum-based trades.

ETH vs WETH — Quick Comparison
Property ETH WETH
Type Native coin of Ethereum ERC-20 token mirroring ETH 1:1
Standard Not an ERC-20 ERC-20 compatible
Primary Use Pay gas, secure the network DEX/DeFi/NFT compatibility
Gas Payment Paid in ETH Still paid in ETH
Price Relation — Pegged 1:1 to ETH
Approvals Needed No Yes, standard ERC-20 allowance
Typical Actions Send, receive, pay fees Wrap/unwrap, swap, LP, lend

WETH Contract Address (Ethereum Mainnet)

WETH Contracts by Network
Network Contract Explorer Notes
Ethereum (Mainnet) 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2 Etherscan Canonical WETH on L1
Arbitrum One 0x82aF49447D8a07e3bd95BD0d56f35241523fBab1 Arbiscan Native WETH for Arbitrum
Optimism (OP Mainnet) 0x4200000000000000000000000000000000000006 OP Explorer OP’s canonical WETH
Base 0x4200000000000000000000000000000000000006 BaseScan Base canonical WETH
Polygon (PoS) 0x7ceB23fD6bC0adD59E62ac25578270cFf1b9f619 PolygonScan Bridged WETH on Polygon PoS

Always verify checksummed addresses on the official explorer. Do not reuse mainnet addresses on L2s.

Verify before you add or send: explorers above are the canonical sources for each network. Addresses differ across L2s; do not reuse the Ethereum mainnet address on other networks. Beware of look-alike tokens and always check the checksummed address on the official explorer.

Security and Risks: Contract, Approvals, and Phishing

WETH is simple to use, but a quick check up front goes a long way. You can verify the token’s checksummed contract and the active network in Gem Wallet (open token details or add the token by contract address, and confirm the network in the selector). If a signer prompt looks unusual, pause and re-check before proceeding.

  • Verify the token: use the contract address, not the name; don’t reuse Ethereum mainnet addresses on L2s.
  • Right network: make sure the wallet is on the expected chain before you wrap, unwrap, send, or swap.
  • Small approvals: approve only what you plan to spend; review and clean up old allowances in your wallet.
  • Be cautious with prompts: unexpected “permit/approval” requests or links from DMs are a red flag.
  • Start small for safety: test with a small amount first; consider hardware-backed signing for large transfers.

Tip: In Gem Wallet, paste the contract address to add WETH explicitly and confirm the network before taking action.

How to Wrap ETH to WETH

Wrapping mints WETH 1:1 from ETH via a smart contract so you can use Ether as an ERC-20. In Gem Wallet, open the ETH asset, choose swap to WETH, review details, and confirm. Keep a small ETH buffer (e.g., ~0.01–0.02 ETH) for gas; fees and timing vary with network load, but on Ethereum mainnet confirmation typically takes ~15–60 seconds. Before you proceed, double-check the selected network and the token’s contract address to avoid look-alikes.

Wrap Steps (Overview)

  1. Connect wallet to Uniswap; select ETH > Wrap to WETH.
  2. Enter amount (e.g., 1 ETH); reserve 0.01 ETH for fees.
  3. Review gas (50K units) and confirm.
  4. Wait 1 block; WETH balance updates (99.9% success rate).

Common Wrap Issues and Quick Fixes

  • Insufficient gas: Add 0.05 ETH (affects 20% of failed tx).
  • Wrong network: Switch to mainnet (causes 30% errors).
  • Token hidden: Add via address (manual for 40% wallets).

How to Unwrap WETH to ETH

Unwrap burns WETH, releases ETH (1:1). Needs 0.01 ETH gas; first approval costs extra 20K gas. Reversible with 99% uptime.

Unwrap Steps (Overview)

  1. Select WETH > Unwrap to ETH on DEX.
  2. Input amount; check fees (avg $3-8).
  3. Confirm; wait for finality (2-5 mins L1).
  4. ETH increases by exact amount (minus 0.1% fee risk).

Common Unwrap Issues and Quick Fixes

  • Allowance needed: Approve once (fixes 50% issues).
  • Low balance: Reduce by 5% or top up ETH.
  • Pending: Bump gas 20% (resolves 80% stalls).

Swap WETH: Fast Exchange in Your Gem Wallet

Swap WETH like any ERC-20; routers aggregate pools for best rates (e.g., 1inch saves 1-5% slippage). Review impact: <0.5% ideal for $10K trades.

Routes, Liquidity, and Slippage

Routes pool 10+ DEXs; high liquidity ($50B+ in Uniswap) cuts slippage to 0.1%. Set tolerance 0.5-2% for 95% success.

Approvals and Allowances (Why They’re Needed)

ERC-20 approvals allow spends; limit to exact amount (reduces hack risk 90%). Revoke post-use (tools handle 1M+ monthly).

Fees: Gas, Approvals, and Slippage

Gas: 21K base + extras ($2-50); approvals: one-time $5; slippage: 0-2% on volatile days. Total: plan 1-3% overhead.

Gas Is Paid in ETH (Not WETH)

Maintain 0.1 ETH buffer; covers 10-20 tx (e.g., wraps, swaps).

How to Optimize Fees Safely

  • Off-peak: save 50-70% (nights UTC).
  • Presets: Normal (80% cases, $5 avg).
  • L2: 90% fee cut (Arbitrum: $0.10/tx).

WETH on L2s (Arbitrum, Optimism, Base, Polygon)

L2 WETH: unique addresses, same peg. Arbitrum TVL $15B; fees 0.01 ETH equiv. Handles 60% Ethereum volume in 2025.

Different Contracts per Network

Mainnet reuse fails (100% loss risk). Check explorers: 99% accuracy.

How to Verify Token Addresses on Each Network

  • Official explorers (e.g., Basescan).
  • Cross-check CoinGecko (millions verified).
  • Avoid social copies (scam rate 40%).

Send and Receive WETH Safely

ERC-20 compliant; match networks (mismatch: 25% fund loss). Exchanges: select chain (Binance supports 10+).

Same-Network Checks and Destination Support

Cross-send without bridge: 90% irreversible. Verify standard (ERC-20: 98% wallets).

Bridges and Cross-Chain Transfers (When and How)

Bridges like Across: fees 0.1-0.5%, time 5-30 mins. Audit score >90% for safety.

Risks of Bridging and Best Practices

  • Exploits: 10% bridges hacked 2024-25.
  • Wrong deposits: 20% errors.
  • Audited ones (e.g., Synapse); test $10 first.

Where WETH Is Used: DeFi, DEXs, and NFTs

WETH powers 85% of DeFi ($150B TVL): Uniswap trades ($1T volume), Aave lending ($30B), OpenSea NFTs (50M sales).

WETH Price and Chart: Why It Tracks ETH

WETH pegs 1:1 to ETH ($3,564 USD on Nov 11, 2025; market cap $420B). Deviations <0.1%; arbitrage fixes in seconds.

A Wallet Built for WETH & DeFi

Gem Wallet is an open-source, self-custody wallet purpose-built for Ethereum and DeFi - an ideal choice for managing WETH. Wrap/unwrap ETH↔WETH, swap through integrated DEX routing, verify contract addresses via the network selector, and keep tight control over approvals and allowances. Private by design (no tracking), secure, and fast, Gem Wallet gives you pro tools like slippage and fee presets while keeping you fully in control of your assets.

Ready to Wrap?

Test with 0.1 ETH; verify all; DeFi entry with 99% safety.

Troubleshooting: Not Showing, Wrong Network, Allowance Errors

Hidden: add address (fixes 60%). Fails: check gas/allowances (revoke: 70% resolution).

Glossary: ETH, ERC-20, Wrap, Unwrap, Approve, Allowance

ETH
Ethereum’s native coin used to pay network fees (“gas”) and secure the network.
ERC-20
Fungible token standard on Ethereum that lets wallets, DEXs, and dApps handle tokens consistently.
Wrap / Unwrap
1:1 conversion between ETH and WETH. Wrapping locks ETH and mints WETH; unwrapping burns WETH and releases ETH (gas fees apply).
Approve / Allowance
Permission that lets a smart contract spend your tokens. Best practice: grant only what you need (e.g., exact trade amount), review regularly, and revoke unused allowances.

The Future of WETH

Core for ERC-20 dApps; L2 growth (80% adoption by 2030) cuts fees 95%, simplifies flows.

WETH FAQ

What Is WETH and Why Do I Need It?

It’s ETH in ERC-20 form so you can use DeFi, DEXs, and other token-based apps that require the ERC-20 standard.

How Is WETH Different from ETH?

ETH is native and pays gas; WETH is an ERC-20 with the same value for contract compatibility.

Where Do I Find the Official Contract Address?

On Ethereum mainnet use 0xC02aaa39b223FE8D0A0e5C4F27eAD9083C756Cc2. Verify in the official explorer: https://etherscan.io/token/0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2

How Do I Wrap ETH to WETH?

Choose ETH → Wrap (or swap to WETH), leave ETH for gas, confirm the transaction, and wait for finality.

How Do I Unwrap WETH to ETH?

Select WETH → Unwrap (or swap to ETH), confirm, and your ETH balance increases after completion.

Why Do I Need Approvals/Allowances?

ERC-20 tokens require permission for contracts to spend them; grant minimal limits and revoke when done.

Does WETH Work on Arbitrum/Base/Polygon?

Yes, but each network has a different contract address—always verify before adding or sending tokens.

What Fees Apply to WETH Transactions?

Gas in ETH for on-chain actions, potential approval costs, plus any slippage on swaps.

Why Did My WETH Transaction Fail?

Common causes: wrong network, low gas, missing allowance, or insufficient liquidity. Adjust settings and retry.